title: Organ size increases with weight gain in power-trained athletes.
abstract: The purpose of this study was to determine whether overfeeding and high-intensity physical training increase organ mass. We examined this question using cross-sectional and longitudinal studies in which we measured collegiate male American football players. Freshman (n = 10) and senior players in their second and third years of college (n = 17) participated in the cross-sectional study. The same measurements of the same freshman players (n = 10) were assessed after the one-year weight gain period in the longitudinal study. Fat-free mass (FFM), skeletal muscle, and adipose tissue mass were obtained using dual-energy X-ray absorptiometry. Liver, kidney, brain, and heart volumes were calculated using magnetic resonance imaging or echocardiography. Compared with the freshman players, the senior players had 10.8 kg more FFM, and 0.29 kg, 0.08 kg, and 0.09 kg greater liver, heart, and kidney mass, respectively. In the longitudinal study, FFM, liver, heart, and kidney mass of the freshman players increased by 5.2 kg, 0.2 kg, 0.04 kg, and 0.04 kg, respectively, after one year of overfeeding and physical training. On the other hand, the organ-tissue mass to FFM ratio did not change, except for the brain, in either the cross-sectional or longitudinal studies. Our results indicated that the organ-tissue masses increased with overfeeding and physical training in male collegiate American football players.
authors.affiliation: Graduate School of Sport Sciences, Waseda University, Saitama, Japan.
authors.forename: Sakiho
authors.initials: S
authors.lastname: Miyauchi
authors.forename: Satomi
authors.initials: S
authors.lastname: Oshima
authors.forename: Meiko
authors.initials: M
authors.lastname: Asaka
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kawano
authors.forename: Suguru
authors.initials: S
authors.lastname: Torii
authors.forename: Mitsuru
authors.initials: M
authors.lastname: Higuchi
mesh_terms: D015502:Absorptiometry, Photon; D000273:Adipose Tissue; D000293:Adolescent; D056352:Athletes; D054874:Athletic Performance / Q000502:physiology*; D001823:Body Composition; D003430:Cross-Sectional Studies; D005538:Football; D006321:Heart / Q000502:physiology; D006801:Humans; D006963:Hyperphagia / Q000378:metabolism; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008137:Longitudinal Studies; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism; D009929:Organ Size / Q000502:physiology*; D010807:Physical Endurance / Q000502:physiology*; D064133:Sports Nutritional Physiological Phenomena; D015430:Weight Gain / Q000502:physiology*; D055815:Young Adult